Electromagnetic cooker

Abstract

To improve a cooling efficiency of an electromagnetic cooker.SOLUTION: An electromagnetic cooker 1 includes: a casing 2 that forms an internal space 15 including a first space 31 and a second space 32; a heating coil 4 disposed in the first space 31; a heat sink 27 disposed in the second space 32; an electronic component at least partially disposed in the second space 32; a partition wall 41 that partitions the first space 31 and the second space 32; an intake port 38 that is provided in the casing 2 and allows air to flow into an internal space 15 from the outside of the casing 2; a first fan 25 that is disposed in the internal space 15, sucks air from the intake port 38, and blows the air into the first space 31; a second fan 26 that is disposed in the internal space 15, sucks air from the intake port 38, and blows the air into the second space 32; a first exhaust port 39A that is provided in the casing 2 and is capable of discharging air from the first space 31; and a second exhaust port 39B that is provided in the casing 2 and opens to the second space 32.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an induction cooker. [Background technology]

[0002] Patent Document 1 discloses a tabletop induction cooker that includes a thin, box-shaped main body, a top plate placed on the main body to cover the top opening of the main body, and a concentric heating coil placed inside the main body. When a high-frequency current flows through the heating coil, eddy currents are induced in the bottom of a cooking vessel placed on the top plate, and the cooking vessel is heated by Joule heat.

[0003] The main body is provided with a heating coil, a heat dissipation section, a power supply circuit, a first fan, and a second fan inside. The main body is provided with a first circulation section that guides air from the first fan and a second circulation section that guides air from the second fan. The heating coil is disposed in the first circulation section, and the heat dissipation section is disposed in the second circulation section. The air guided by the first circulation section and the air guided by the second circulation section are joined inside the main body. The joined air is discharged to the outside of the main body through an exhaust port formed in a side wall of the main body. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-159038 Summary of the Invention [Problem to be solved by the invention]

[0005] There is a risk that hot air will be generated when the air that has passed through the heating coil and the air that has passed through the heat dissipation section meet, and that this hot air will be blown onto the circuit components that make up the power supply circuit, which could prevent the circuit components from being cooled efficiently.

[0006] An object of the present invention is to improve the cooling efficiency of an induction cooker. [Means for solving the problem]

[0007] One aspect of the present invention provides an induction cooker comprising: a casing that forms an internal space including a first space and a second space; a heating coil arranged in the first space; a heat sink arranged in the second space; an electronic component at least a portion of which is arranged in the second space; a partition wall that separates the first space from the second space; an air intake port provided in the casing that allows air to flow from outside the casing into the internal space; a first fan that is arranged in the internal space and draws in air from the air intake port and blows it into the first space; a second fan that is arranged in the internal space and draws in air from the air intake port and blows it to the second space; a first exhaust port that is provided in the casing and can exhaust air from the first space; and a second exhaust port that is provided in the casing and opens to the second space.

[0008] According to the above configuration, the internal space of the casing includes a first space in which the heating coil is disposed and a second space in which the heat sink is disposed, and the first space and the second space are separated from each other by a partition wall. This "separation" includes cases in which the spaces are completely airtightly separated from each other and cases in which the spaces are partially separated from each other (i.e., there is a spatial connection between them). Air discharged from the first fan is supplied to the first space to cool the heating coil, and after passing the heating coil, can be discharged to the outside of the casing through the first exhaust port. Air discharged from the second fan is supplied to the second space to cool the heat sink and electronic components, and after passing through these, can be discharged to the outside of the casing through the second exhaust port. Therefore, for example, it is possible to prevent hot air after passing the heating coil from being blown onto electronic components disposed in the second space, improving the cooling efficiency of the induction cooker.

[0009] The internal space may include a third space adjacent to the first space in which some of the electronic components are arranged, and the induction cooker may further include a diversion section that guides some of the air from the first fan to the first space and some of the air to the third space, and the first exhaust port may open to the third space.

[0010] According to the above configuration, the air from the first fan is divided into the first space and the third space. The air divided by the dividing section can be blown onto the electronic components arranged in the third space. This improves the cooling efficiency of the induction cooker.

[0011] The casing may be provided with an exhaust partition wall disposed between the second space and the third space, and the first exhaust port and the second exhaust port may be disposed on opposite sides of the exhaust partition wall.

[0012] According to the above configuration, it is possible to suppress the flow of air between the second space and the third space, making it easier to guide the air in the third space to the first exhaust port and easier to guide the air in the second space to the second exhaust port.

[0013] The internal space may include a common intake space to which both the inlet of the first fan and the inlet of the second fan are open, and the intake ports may be provided at multiple locations on the casing and open into the common intake space.

[0014] According to the above configuration, when two fans are installed inside the casing of an induction cooker, air outside the casing flows into a common air intake space through the air intake ports, and air in the common air intake space is drawn into the inlets of the two fans. The air intake ports are provided in multiple locations. Therefore, even if one of the air intake ports is blocked during cooking using the induction cooker, air outside the casing can be guided to both fans, maintaining cooling performance.

[0015] The air intake may include a bottom air intake portion provided in a bottom wall of the casing.

[0016] With this configuration, air can be taken in from the outside below the casing. Also, since the bottom wall has a larger area than the peripheral wall, it is easy to increase the area of ​​the bottom intake section. Therefore, it is easy to maintain cooling performance.

[0017] The air intake may include a side air intake portion provided in a peripheral wall of the casing.

[0018] According to the above configuration, air can be taken in from the outside of the casing, making it easier to maintain cooling performance.

[0019] The induction cooker may further include a sensor positioned radially away from the center of the heating coil for detecting the temperature of a cooking utensil placed on the induction cooker, and a coil bobbin supporting the heating coil, wherein the coil bobbin includes a boss portion positioned at the center, a rim portion positioned on the outer periphery of the boss portion, a plurality of spoke portions radially connecting the boss portion and the rim portion, and a blocking portion blocking the space between two specific adjacent spoke portions of the plurality of spoke portions, and the sensor may be attached to the upper surface side of the blocking portion.

[0020] With this configuration, the blocking portion can prevent air from the underside of the coil bobbin from passing through to the upper side, thereby suppressing the flow of hot air around the sensor. This makes the sensor less susceptible to the temperature of the heating coil or the hot air, improving the accuracy of detecting the temperature of the cooking utensil.

[0021] The first fan and the second fan may be disposed on an outer circumferential side of the coil bobbin, and the sensor may be disposed between the first fan and the second fan in the circumferential direction of the coil bobbin.

[0022] According to the above configuration, the sensor is placed in an area that is less susceptible to the influence of the air from the first fan and the second fan, which makes the sensor less susceptible to the temperature of the hot air, improving the accuracy of detecting the temperature of the cooking utensil. [Effects of the Invention]

[0023] According to the present invention, the cooling efficiency of an induction cooker can be improved. [Brief explanation of the drawings]

[0024] [Figure 1] 1 is a perspective view showing an electromagnetic cooker according to an embodiment as viewed from above; [Figure 2] Exploded view of an induction cooker. [Figure 3] FIG. 2 is a plan view of the induction cooker with the top plate and upper case removed. [Figure 4] Enlarged view of a portion of Figure 3. [Figure 5] Enlarged view of a portion of Figure 3. [Figure 6] FIG. 4 is a perspective view showing the fan and coil support structure as viewed from the bottom side. [Figure 7] FIG. 2 is a perspective view showing the substrate, the fan, and the coil support structure as viewed from the bottom side. [Figure 8] FIG. 2 is an exploded perspective view of electrical components built into the induction cooker. [Figure 9] FIG. 4 is an exploded perspective view of a coil bobbin and a temperature sensor. [Figure 10] FIG. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, embodiments will be described with reference to the drawings. Note that the same or corresponding elements are designated by the same reference numerals throughout the drawings, and detailed descriptions thereof will be omitted.

[0026] Referring to Figure 1, the induction cooker 1 according to the embodiment is a so-called tabletop type, and is rectangular in plan view. In the following description, the extension direction of one pair of opposite sides of the rectangle is referred to as the width direction W, the extension direction of the other pair of opposite sides is referred to as the depth direction D, and the direction perpendicular to both of these directions is referred to as the height direction H. When the induction cooker 1 is placed horizontally on a table, the width direction W and the depth direction D are oriented horizontally, and the height direction H is oriented vertically.

[0027] An operating unit 9 that is operated by the user is provided on the top surface of the induction cooker 1. The operating unit 9 is located at one end in the depth direction D and is elongated in the width direction W. In the following description, one side in the depth direction D will be referred to as the "front" and the opposite side as the "rear." The "right" is one side in the width direction W, and is the right side of the induction cooker 1 when a user facing the induction cooker 1 from the front looks down on it from above. The "left" is the other side in the width direction W. However, this concept of direction is merely an example and can be changed as appropriate depending on the posture of the induction cooker 1, etc.

[0028] 1 to 5, an induction cooker 1 includes a casing 2, a top plate 3, and a heating coil 4.

[0029] The casing 2 is composed of a lower case 11 and an upper case 12 above the lower case 11. The casing 2 has a rectangular, flat bottom wall 13, a peripheral wall 14 extending upward from the bottom wall 13, an internal space 15 defined by the inner surfaces of the bottom wall 13 and the peripheral wall 14, a flange 16 protruding from the upper end of the peripheral wall 14 toward the inside of the casing 2, and an upper opening 17 defined by the flange 16 and opening the internal space 15 upward.

[0030] The lower case 11 is tray-shaped and includes a bottom wall 13 and peripheral walls 14. The bottom wall 13 is rectangular in plan view, and the peripheral edge of the bottom wall 13 defines the outline of this rectangular shape. The peripheral walls 14 include a front wall 14a extending in the width direction W on the front side, a rear wall 14b extending in the width direction W on the rear side, a right wall 14c extending in the depth direction D on the right side, and a left wall 14d extending in the depth direction D on the left side.

[0031] The upper case 12 forms a flange 16 and defines an upper opening 17. The upper case 12 is fitted from above onto the upper end of the lower case 11, more specifically onto the upper end of the peripheral wall 14. The lower case 11 and the upper case 12 are assembled to each other with a plurality of bolts 8 (see FIG. 2) that are inserted upward from the lower outside of the bottom wall 13.

[0032] The top plate 3 is attached to the casing 2 from above so as to close the upper opening 17. The lower surface of the peripheral edge of the top plate 3 is in close contact with the upper surface of the flange 16. The lower surface of the top plate 3, in the portion covering the upper opening 17, defines an internal space 15 together with the bottom wall 13 and the peripheral wall 14.

[0033] The heating coil 4 is housed in the internal space 15 and is adjacent to the underside of the top plate 3. A plug receptacle 5 is attached to the rear left corner of the casing 2. A magnetic plug 6a attached to one end of a power cord 6 is removably attached to the plug receptacle 5. When the male plug (not shown) attached to the other end of the power cord 6 is connected to a commercial power source with the magnetic plug 6a attached to the plug receptacle 5, commercial power is input to the plug receptacle 5 via the power cord 6, and the induction cooker 1 can operate using the commercial power. Power is supplied to the heating coil 4 through the user's operation of the operating unit 9. This allows induction heating to occur in a cooking container (not shown) placed on the top surface of the top plate 3.

[0034] 2 and 3, the internal space 15 accommodates the heating coil 4 as well as a substrate 20. The substrate 20 is equipped with a heating circuit for energizing the heating coil 4 to heat the cooking vessel.

[0035] The heating circuit is composed of a wiring pattern printed on a substrate 20 and numerous electronic components mounted on the substrate 20. The electronic components include, for example, a diode bridge 21 that converts AC from a commercial power source into DC, a transistor 22 that adjusts the amount and frequency of the current passed through the heating coil 4, an IC chip 23 that functions as a controller that controls the operation of the transistor 22, and a plurality of capacitors 24 for smoothing or resonance. The transistor 22 is, for example, an IGBT (insulated gate bipolar transistor). At least some of the capacitors 24 are electrolytic capacitors.

[0036] During operation of the induction cooker 1, the heating coil 4 and several electronic components that make up the heating circuit generate heat. To dissipate heat, the internal space 15 also accommodates a first fan 25, a second fan 26, and a heat sink 27. This prevents unstable operation of the heating circuit due to heat and prevents deterioration of the electronic components. Examples of electronic components that generate a lot of heat include the diode bridge 21, the transistor 22, and the IC chip 23. An example of an electronic component whose operation may become unstable due to heat is the IC chip 23. An example of an electronic component whose deterioration is accelerated by heat is the capacitor 24 (particularly, an electrolytic capacitor). Note that only the housings of the first fan 25 and the second fan 26 are shown, and the impellers rotatably supported by the housings are not shown.

[0037] The internal space 15 is partitioned into multiple spaces. The multiple spaces include a common air intake space 30, a first space 31, a second space 32, and a third space 33. The common air intake space 30 is formed in the right portion (one side in the width direction W) of the internal space 15. The first space 31 is adjacent to the left portion (the other side in the width direction W) of the common air intake space 30. The second space 32 is adjacent to the left side of the front end portion (one end portion in the depth direction D) of the common air intake space 30, and is adjacent to the front and left sides of the first space 31. The third space 33 is adjacent to the left side of the rear end portion of the common air intake space 30, and is adjacent to the rear and left sides of the first space 31. The left portion of the second space 32 and the left portion of the third space 33 are adjacent to each other in the front-to-rear direction (depth direction D). The second space 32 and the third space 33 are separated by an exhaust partition wall 37 provided in the casing 2, more specifically, an exhaust partition wall 37 protruding from the lower surface of the flange 16 of the upper case 12. The exhaust partition wall 37 is disposed between the second space 32 and the third space 33.

[0038] The first fan 25 and the second fan 26 are housed in a common air intake space 30. The common air intake space 30 does not house the circuit board 20, the heating coil 4, or the electronic components attached to the circuit board 20. Electrical components other than these fans are housed in the first space 31, the second space 32, or the third space 33. In the following description, the first space 31, the second space 32, and the third space 33 may be collectively referred to as the electrical component housing space.

[0039] The heating coil 4 and a coil support structure that supports the heating coil 4 are housed in the first space 31. The heating coil 4 has a double annular shape with concentric inner and outer rings, and the first space 31 has a circular shape in a plan view.

[0040] The substrate 20 is formed in a U-shape in a plan view, and is arranged in the second space 32 and the third space 33 with the U-shape open to the right. The heating coil 4 is arranged in the center of the U-shape, and the substrate 20 barely overlaps the heating coil 4 in a plan view (although part of the outer periphery of the heating coil 4 may overlap the substrate 20 in the height direction H).

[0041] The heat sink 27, the diode bridge 21, the transistor 22, and the IC chip 23 are housed in the second space 32. At least a portion of the capacitor 24 is housed in the third space 33. The heat sink 27 is in contact with the diode bridge 21 and the transistor 22, and promotes heat dissipation from the diode bridge 21 and the transistor 22.

[0042] The plug receptacle 5 is accommodated in a plug receptacle accommodating space 34 that is separated from the electrical equipment accommodating space (particularly the third space 33) by a plug partition wall 35. The plug receptacle accommodating space 34 is located in the rear left corner of the internal space 15.

[0043] The first fan 25 and the second fan 26 are low-profile blower fans whose axial direction is oriented in the height direction H. The blower fans can obtain high static pressure, so they can create a sufficient airflow even in the interior space 15 where ventilation resistance is high due to the dense arrangement of parts to be cooled.

[0044] The first fan 25 has an inlet for drawing in air and an outlet for discharging air. An inlet is provided on each of the bottom and top surfaces of the first fan 25, allowing the first fan 25 to draw air upward from its bottom surface and downward from its top surface. The outlet is a long, narrow rectangle with one pair of opposite short sides oriented in the height direction H and another pair of opposite long sides oriented horizontally. The first fan 25 is supported by the casing 2 in a state slightly elevated above the inner upper surface of the bottom wall 13. The inlet on the bottom surface opens into the gap between the bottom surface of the first fan 25 and the inner upper surface of the bottom wall 13, and the inlet on the top surface opens into the gap between the top surface of the first fan 25 and the lower surface of the top plate 3.

[0045] The second fan 26 is similarly configured and arranged. It also has a pair of inlets on the bottom and top surfaces and a low-profile rectangular outlet on the side. The second fan 26 is larger than the first fan 25 and can blow air with a larger air volume and static pressure.

[0046] The common intake space 30 is defined by the right wall 14c, the right end of the rear wall 14b, and the first, second, and third intake partitions 36a, 36b, and 36c that extend upright from the bottom wall 13. The first intake partition 36a protrudes forward from the inner surface of the left portion of the rear wall 14b. The second intake partition 36b protrudes leftward from the inner surface of the front end of the right wall 14c. The third intake partition 36c extends in the depth direction D, moving away from the right wall 14c to the left and sloping leftward as it extends forward. The front end of the third intake partition 36c is located to the right and forward of the first intake partition 36a. The leading ends of the first and second intake partitions 36a and 36b and the rear end of the third intake partition 36c are located at approximately the same position in the width direction W. The rear end of the third intake partition 36c is located rearward of the second intake partition 36b.

[0047] The common air intake space 30 is surrounded by the right surface of the first air intake partition 36a, the portion of the inner surface of the rear wall 14b between the first air intake partition 36a and the right wall 14c, the portion of the inner surface of the right wall 14c between the rear wall 14b and the second air intake partition 36b, the rear surface of the second air intake partition 36b, and the right surface of the third air intake partition 36c. The first fan 25 is housed in the rear end of the common air intake space 30. The outlet of the first fan 25 is located between the leading edge of the first air intake partition 36a and the rear end of the third air intake partition 36c, and extends at an angle rearward as it moves leftward. The second fan 26 is housed in the front end of the common air intake space 30. The outlet of the second fan 26 is located between the leading edge of the second air intake partition 36b and the front end of the third air intake partition 36c, and extends along the depth direction D.

[0048] Although not shown in detail, packing is provided across the upper end of the first intake partition 36a, the upper edge of the outlet of the first fan 25, the upper end of the third intake partition 36c, the upper edge of the outlet of the second fan 26, and the upper end of the second intake partition 36b. This seals the common intake space 30 from the electrical equipment housing space, preventing air discharged from the first fan 25 and the second fan 26 from returning to the common intake space 30.

[0049] The casing 2 is provided with an intake port 38 for allowing air to flow into the internal space 15 from the outside of the casing 2, and an exhaust port 39 for allowing air to flow out from the internal space 15 to the outside of the casing 2. Both the intake port 38 and the exhaust port 39 are realized by a large number of slits that penetrate multiple parts of the casing 2. Each slit is roughly in the shape of an elongated rectangle.

[0050] The air intake port 38 opens into the common air intake space 30. The air intake port 38 includes a bottom air intake section 38A provided in the bottom wall 13 of the casing 2 and a side air intake section 38B provided in the peripheral wall 14 of the casing 2. The side air intake section 38B is provided in the entire portion of the peripheral wall 14 that defines the common air intake space 30 (i.e., the entire area of ​​the right wall 14c rearward of the second air intake partition 36b and the entire area of ​​the rear wall 14b to the right of the first air intake partition 36a). The bottom air intake section 38A includes a first bottom air intake section directly below and around the first fan 25 and a second bottom air intake section directly below and around the second fan 26.

[0051] A plurality of legs are distributed on the bottom of the casing 2, and when the bottom surfaces of the legs are supported on a table, a gap is formed between the outer lower surface of the bottom wall 13 and the table. In other words, when the induction cooker 1 is in use, the bottom air intake section 38A is fully open to the space outside the casing 2.

[0052] Both the first fan 25 and the second fan 26 draw in air taken into the common air intake space 30 from outside the casing 2 through the air intake port 38. The first fan 25 draws in air from the first bottom air intake section, and the second fan 26 draws in air from the second bottom air intake section. The second bottom air intake section is also provided in an area rearward of the second fan 26 in a plan view, so the first fan 25 can also draw in air from the second bottom air intake section. Both the first fan 25 and the second fan 26 discharge air in a horizontal direction perpendicular to the extension direction of the outlet, toward the opposite side to the common air intake space 30.

[0053] The first fan 25 discharges air in a direction inclined in both the depth direction D and the width direction W, so that the air moves forward as it moves leftward. Part of the air from the first fan 25 is blown into the first space 31, and part of the air from the first fan 25 is guided to the third space 33. The second fan 26 discharges air to the left. The air from the second fan 26 is blown into the second space 32 and flows tangentially near the front end of the heating coil 4.

[0054] The exhaust ports 39 include a first exhaust port 39A capable of exhausting air from the first space 31 and a second exhaust port 39B that mainly exhausts air from the second space 32. The first exhaust port 39A opens to the third space 33, and the second exhaust port 39B opens to the second space 32. The first space 31 is disposed in the center of the internal space 15 and communicates with the adjacent third space 33, so that air flowing through the first space 31 flows into the third space 33. The first exhaust port 39A exhausts air from the third space 33, including air from the first space 31. In other words, the first exhaust port 39A mainly exhausts air that has been discharged from the first fan 25 and passed through the first space 31 or the third space 33, and the second exhaust port 39B mainly exhausts air that has been discharged from the second fan 26 and passed through the second space 32.

[0055] Both the first exhaust port 39A and the second exhaust port 39B are provided in the peripheral wall of the casing 2, particularly in the left wall 14d. As described above, the second space 32 and the third space 33 are partially separated by the exhaust partition wall 37 in the left part of the internal space 15. The first exhaust port 39A is formed by one of the many slits provided in the left wall 14d that is located rearward of the exhaust partition wall 37. The second exhaust port 39B is formed by one of the many slits provided in the left wall 14d that is located forward of the exhaust partition wall 37.

[0056] The exhaust partition wall 37 is disposed so as to separate the first exhaust port 39A and the second exhaust port 39B provided in the left wall 14d, and the first exhaust port 39A and the second exhaust port 39B are disposed on opposite sides of the exhaust partition wall 37 in the depth direction D. The exhaust partition wall 37 does not completely airtightly isolate the second space 32 and the third space 33, but it does create a large airflow resistance between the second space 32 and the third space 33. Therefore, substantially no airflow occurs between the second space 32 and the third space 33, and air in the third space 33 is more likely to be guided to the first exhaust port 39A, and air in the second space 32 is more likely to be guided to the second exhaust port 39B.

[0057] The heating coil 4 is supported by a coil support structure attached to the casing 2. The coil support structure is provided with a partition wall 41 that defines the first space 31 or separates the first space 31 from the second space 32, and a diverter 42 that guides air from the first fan 25 into the first space 31 and guides a portion of the air to the third space 33.

[0058] Referring to FIG. 8 , the coil support structure mainly includes a coil bobbin 43 that supports a heating coil 4 and a plurality of ferrite cores 44. The coil support structure includes a shield plate 45 and a lower insulating plate 46 interposed between the coil bobbin 43 and the bottom wall 13 of the casing 2, and further includes an upper insulating plate 47 interposed between the coil bobbin 43 and the heating coil 4. The shield plate 45, the lower insulating plate 46, the coil bobbin 43, the upper insulating plate 47, and the heating coil 4 are stacked in this order from the bottom. The ferrite core 44 is housed in a groove formed in the coil bobbin 43, and the upper insulating plate 47 covers the ferrite core 44 from above. In this embodiment, a partition wall 41 and a flow dividing portion 42 are provided on the coil bobbin 43. The lower insulating plate 46 and the upper insulating plate 47 are made of, for example, mica.

[0059] Referring to FIG. 9, the coil bobbin 43 has a cylindrical boss portion 43a disposed at the center, a ring-shaped rim portion 43b concentric with the boss portion 43a, and a plurality of spoke portions 43c connecting the boss portion 43a and the rim portion 43b. In this embodiment, six spoke portions 43c are radially arranged at equal intervals in the circumferential direction. Each spoke portion 43c has a groove for accommodating one ferrite core 44. A fan-shaped gap 43d is formed between two adjacent spoke portions 43c, and the coil bobbin 43 has a blocking portion 43e that blocks the gap between two specific adjacent spoke portions 43c. Therefore, the number of gaps 43d is one less than the number of spoke portions 43c (five in this example).

[0060] The induction cooker 1 is equipped with a temperature sensor for detecting the temperature of a cooking container placed on the upper surface of the top plate 3. In this embodiment, two temperature sensors are provided. One is a center sensor 51 attached to the boss portion, and the other is a side sensor 56 attached to the upper surface of the closing portion 43e. Both temperature sensors are realized, for example, by thermistors, and a pair of lead wires 51a, 56a extend from each temperature sensor. By arranging the temperature sensors not only at the center but also at positions radially away from the center, the temperature of the cooking container can be accurately detected by either sensor even if the center of the cooking container is eccentric from the center of the heating coil 4 or if the bottom of the cooking container is recessed upward at the center.

[0061] A center holder 52 that holds a center sensor 51 is fitted into the boss portion 43a. The center sensor 51 is supported on the upper surface side of the center holder 52, and a pair of lead wires 51a pass downward from the center sensor 51 through the center holder 52. The center holder 52 holds a fuse 53 together with the center sensor 51. The fuse 53 and the lead wires connected to it are held in a horizontal position, opposite to the lead wires 51a of the center sensor 51.

[0062] A side holder 57 that holds a side sensor 56 is fitted into the upper surface of the blocking portion 43e. The side sensor 56 is also held by the side holder 57 and attached to the upper surface of the blocking portion 43e via the side holder 57. As with the center sensor 51, a pair of lead wires 57a passes downward from the side sensor 56 through the side holder 57.

[0063] The upper insulating plate 47 has the same shape as the coil bobbin 43 in plan view except that it does not have the closed portion 43e, and there are six gaps between adjacent spokes. The heating coil 4 is attached to the upper surface side of the upper insulating plate 47.

[0064] 4, center sensor 51 is exposed upward through the center hole of upper insulating plate 47 and the center hole of the inner ring of heating coil 4. Side sensor 56 is exposed upward through a gap in upper insulating plate 47 and a gap between the inner ring and outer ring of heating coil 4. This upward exposure allows the temperature sensor to be in close proximity to or in contact with the underside of top plate 3, enabling accurate detection of the temperature of the cooking vessel.

[0065] 3, the first fan 25 and the second fan 26 are disposed on the outer periphery of the heating coil 4 (and the coil support structure). The side sensor 56 is disposed between the first fan 25 and the second fan 26. In this regard, two of the six spokes of the coil bobbin 43 and the upper insulating plate 47 extend forward and backward from the center of the coil bobbin 43 without inclining in the width direction W. The remaining four are arranged at equal intervals of 60 degrees.

[0066] For ease of explanation, if we imagine a clock position in plan view with the rear of the center of the coil bobbin 43 as the base, with 0 o'clock and the right as 3 o'clock, the six spokes 43c extend horizontally in the 0 o'clock, 2 o'clock, 4 o'clock, 6 o'clock, 8 o'clock, and 10 o'clock directions from the center of the coil bobbin 43. The first fan 25 is disposed approximately in the 1 to 2 o'clock direction with the center of the coil bobbin 43 as the base, and the second fan 26 is disposed approximately in the 4 to 5 o'clock direction with the center of the coil bobbin 43 as the base. The blocking portion 43e is provided between the spokes 43c extending in the 2 o'clock direction and the spokes 43c extending in the 4 o'clock direction, and the side sensor 56 is attached to the upper surface side of the blocking portion 43e.

[0067] Therefore, it can be said that the side sensor 56 is disposed between the first fan 25 and the second fan 26 in the circumferential direction of the coil bobbin 43 (i.e., at the clock position assumed as described above). It can also be said that the side sensor 56 is disposed between the first fan 25 and the second fan 26 in the depth direction D. The air from the first fan 25 is directed toward the center of the coil bobbin 43. The air from the second fan 26 is directed in a tangential direction near the front end (6 o'clock position) of the heating coil 4, and is not supplied to the first space 31 in which the heating coil 4 is disposed. Therefore, it is difficult for the air from the first fan 25, as well as the air from the second fan 26, to be blown directly onto the side sensor 56.

[0068] 3, 6, and 7, the partition wall 41 and the diverter 42 are provided on the underside of the coil bobbin 43. The diverter 42 is disposed opposite the outlet of the first fan 25. The diverter 42 protrudes downward from the underside of the rim 43b and extends circumferentially between the spokes 43c extending in the 0 o'clock direction and the spokes 43c extending in the 2 o'clock direction. The partition 41 also protrudes downward from the underside of the rim 43b. The partition 41 extends in a semicircular arc from the 3 o'clock position (approximately the left end) in a clockwise direction, passing through the 6 o'clock position (approximately the front end), to the 10 o'clock position (approximately the right end). More specifically, the partition 41 includes a main partition 41a extending from the 3 o'clock position to the 9 o'clock position and a sub-partition 41b separated from the main partition 41a and extending from the 9 o'clock position to the 10 o'clock position. A communication portion 41c is provided between the main partition wall 41a and the sub-partition wall 41b, which communicates the third space 33 with the first space 31 (particularly, the space below the heating coil 4).

[0069] Here, the air discharged from the first fan 25 is blown onto the upper and lower surfaces of the coil bobbin 43 on which the heating coil 4 is supported.

[0070] A portion of the air blown onto the underside of the coil bobbin 43 collides with the diverter 42 and is guided by the diverter 42 toward the 4 o'clock direction (front right) on the underside of the coil bobbin 43. The air guided from the diverter 42 toward the 4 o'clock direction passes under the spokes 43c extending in the 4 o'clock direction and flows forward and / or leftward. The partition wall 41 extends linearly at its right end so as to bend radially outward. Therefore, air flowing on the right side is guided toward the inside of the coil bobbin 43. The air on the right side passes under the coil bobbin 43 and may collide with the partition wall 41. The air is guided by the partition wall 41 and flows in the circumferential direction. A portion of the air on the underside flows into the third space 33 via the communication portion 41c. A portion of the air on the underside passes through the gaps between the spokes 43c and flows toward the upper side of the coil bobbin 43. The air on the upper surface side exchanges heat with the heating coil 4 and flows into the third space 33.

[0071] On the other hand, the air blown onto the upper surface of the coil bobbin 43 is prevented from flowing into the second space 32 by the windshield wall 27a of the heat sink 27, as will be described later.

[0072] A portion of the air discharged from first fan 25 collides with diverter 42, is guided by diverter 42, and is guided to the left rear on the underside of coil bobbin 43. A portion of this air on the left side flows into third space 33 from the right side and flows along the upper and lower sides of substrate 20. Many electronic components, such as capacitor 24, are disposed in third space 33. The air flows toward the left side of third space 33 while exchanging heat with capacitor 24 and other electronic components.

[0073] Air that flows through the third space 33 from the right side or passes through the first space 31 and reaches the left part of the third space 33 is discharged to the outside of the casing 2 through the first exhaust port 39A. The presence of the exhaust partition wall 37 reduces the possibility of the air flowing into the second space 32.

[0074] Next, the outlet of the second fan 26 faces the heat sink 27. The heat sink 27 is made of, for example, aluminum or an alloy thereof and has high thermal conductivity. The heat sink 27 is attached to the upper surface of the substrate 20. Electronic components that generate a large amount of heat, such as a diode bridge 21 and a transistor 22, are fastened to the heat sink 27. Both the diode bridge 21 and the transistor 22 are electrically connected to the wiring pattern on the substrate 20 via lead wires.

[0075] The air discharged from the second fan 26 is blown onto the heat sink 27 and passes mainly to the left over the upper surface of the heat sink 27. During this process, the air exchanges heat with the heat sink 27. As a result, heat generated from the diode bridge 21 and the transistor 22 is released into the air via the heat sink 27.

[0076] The air exchanges heat with the electronic components arranged to the left of the heat sink 27, flows further leftward through the second space 32, and is discharged to the outside of the casing 2 through the second exhaust port 39B. The presence of the exhaust partition wall 37 reduces the possibility of the air flowing into the third space 33.

[0077] The heat sink 27 is provided with a windshield wall 27a that protrudes upward from the edge on the side in contact with the coil bobbin 43. This prevents air in the second space 32 from flowing toward the upper surface of the coil bobbin 43. Furthermore, it prevents air flowing above the coil bobbin 43 in the first space 31 from entering the second space 32. In particular, preventing air heated by the heating coil 4 from entering the second space 32 effectively dissipates heat from the heat sink 27 (and consequently the diode bridge 21 and transistor 22).

[0078] As such, the induction cooker 1 of this embodiment comprises a casing 2 that forms an internal space 15 including a first space 31 and a second space 32, a heating coil 4 arranged in the first space 31, a heat sink 27 arranged in the second space 32, electronic components at least a portion of which is arranged in the second space 32, a partition wall 41 that separates the first space 31 and the second space 32, an air intake 38 provided in the casing 2 that allows air to flow from the outside of the casing 2 into the internal space 15, a first fan 25 that is arranged in the internal space 15 and draws in air from the air intake 38 and sends it to the first space 31, a second fan 26 that is arranged in the internal space 15 and draws in air from the air intake 38 and sends it to the second space 32, a first exhaust port 39A provided in the casing 2 that can exhaust air from the first space 31, and a second exhaust port 39B provided in the casing 2 that opens into the second space 32.

[0079] According to the above configuration, the internal space 15 of the casing 2 includes a first space 31 in which the heating coil 4 is disposed and a second space 32 in which the heat sink 27 is disposed, and the first space 31 and the second space 32 are separated from each other by a partition wall 41. The air discharged from the first fan 25 is supplied to the first space 31 to cool the heating coil 4, and after passing the heating coil 4, can be discharged to the outside of the casing 2 through the first exhaust port 39A. The air discharged from the second fan 26 is supplied to the second space 32 to cool the heat sink 27 and electronic components, and after passing through these, can be discharged to the outside of the casing 2 through the second exhaust port 39B. This prevents the hot air after passing the heating coil 4 from being blown onto the electronic components disposed in the second space 32, improving the cooling efficiency of the induction cooker 1.

[0080] The internal space 15 is adjacent to the first space 31 and includes a third space 33 in which some of the electronic components are arranged. The induction cooker 1 further includes a diverter 42 that guides some of the air from the first fan 25 to the first space 31 and some of the air to the third space 33. The first exhaust port 39A also discharges air from the third space 33. This allows the air from the first fan 25 to be diverted between the first space 31 and the third space 33. The diverted air can be blown directly onto the electronic components arranged in the third space 33. This improves the cooling efficiency of the induction cooker 1.

[0081] The casing 2 is provided with an exhaust partition wall 37 disposed between the second space 32 and the third space 33. The first exhaust port 39A and the second exhaust port 39B are disposed on opposite sides of the exhaust partition wall 37. This makes it possible to suppress the flow of air between the second space 32 and the third space 33, making it easier to guide the air in the third space 33 to the first exhaust port 39A and easier to guide the air in the second space 32 to the second exhaust port 39B.

[0082] The internal space 15 includes a common air intake space 30 to which both the inlet of the first fan 25 and the inlet of the second fan 26 are open. Air intake ports 38 are provided in multiple locations on the casing 2 and open to the common air intake space 30. As a result, when two fans are installed inside the casing 2 of the induction cooker 1, air outside the casing 2 flows into the common air intake space 30 through the air intake ports 38, and air in the common air intake space 30 is drawn into the inlets of the two fans. The air intake ports 38 are provided in multiple locations. Therefore, even if some of the air intake ports 38 are blocked during cooking using the induction cooker 1, air outside the casing 2 can be guided to both of the two fans, maintaining cooling performance.

[0083] The air intake 38 is provided in the bottom wall 13 of the casing 2 and includes a bottom air intake section 38A that opens into the common air intake space 30. This allows air to be taken in from the outside below the casing 2. In addition, because the bottom wall 13 has a larger area than the peripheral wall 14, it is easy to make the area of ​​the bottom air intake section 38A large. This makes it easy to maintain cooling performance. The air intake 38 is provided in the peripheral wall 14 of the casing 2 and includes a side air intake section 38B that opens into the common air intake space 30. This allows air to be taken in from the outside of the casing 2, making it easy to maintain cooling performance.

[0084] The induction cooker 1 further includes a side sensor 56 positioned radially away from the center of the heating coil 4 for detecting the temperature of a cooking utensil placed on the induction cooker 1, and a coil bobbin 43 supporting the heating coil 4. The coil bobbin 43 includes a central boss portion 43a, a rim portion 43b positioned on the outer periphery of the boss portion 43a, multiple spoke portions 43c radially connecting the boss portion 43a and the rim portion 43b, and a blocking portion 43e blocking the gap between two adjacent spoke portions 43c. The side sensor 56 is attached to the upper surface of the blocking portion 43e. This prevents air from passing below the coil bobbin 43 from passing to the upper surface. This prevents hot air from flowing around the side sensor 56. The side sensor 56 is less susceptible to the temperature of the heating coil 4 or the hot air, improving the accuracy of detecting the temperature of the cooking utensil.

[0085] The first fan 25 and the second fan 26 are disposed on the outer periphery of the coil bobbin 43. The side sensor 56 is disposed between the first fan 25 and the second fan 26 in the circumferential direction of the coil bobbin 43. This positions the side sensor 56 in an area that is less susceptible to the influence of the air from the first fan 25 and the second fan 26. The side sensor 56 is less susceptible to the temperature of the hot air, improving the accuracy of detecting the temperature of the cooking utensil.

[0086] Although the embodiment has been described above, the checkered pattern can be appropriately changed within the scope of the present invention.

[0087] In the above embodiment, the partition wall 41 separates the first space 31 and the second space 32 on the underside of the heating coil 4, but the first space 31 and the second space 32 may be spatially connected above the heating coil 4. This configuration is merely an example, and the first space 31 and the second space 32 may be completely airtightly separated. The same applies to the second space 32 and the third space 33. The exhaust partition wall 37 may separate the second space 32 and the third space 33 completely airtight. In the above embodiment, the second space 32 is partially separated from the first space 31 and partially separated from the third space 33, but it may be completely separated from both the first space 31 and the third space 33. [Explanation of symbols]

[0088] 1 Induction cooker 2 Casing 3 Top Plate 4 heating coils 5 Plug holder 6 Power cord 6a magnetic plug 9 Control section 11 Lower case 12 Upper case 13 Bottom wall 14 Peripheral wall 14a front wall 14b Back wall 14c Right wall 14d left wall 15 Interior Space 16 flange 17 Top opening 20 PCB 21 Diode bridge (electronic component) 22 Transistor (electronic component) 23 IC chips (electronic components) 24 Capacitor (electronic component) 25 First Fan 26 Second Fan 27 Heatsink 27a Windshield wall 30 Common intake space 31 1st space 32 Second space 33 Third space 34 Plug receptacle accommodation space 35 Plug Partition 36a First intake bulkhead 36b Second intake bulkhead 36c Third intake bulkhead 37 Exhaust bulkhead 38 Air intake 38A Bottom intake 38B side intake 39 Exhaust port 39A First exhaust port 39B Second exhaust port 41 Partition Wall 41a Main partition wall 41b Secondary partition wall 41c Communication part 42 Diversion section 43 Coil bobbin 43a Boss part 43b Rim section 43c spokes 43d gap 43e Occlusion 44 Ferrite core 45 Shield plate 46 Lower insulating plate 47 Upper insulating plate 51 Center sensor 51a lead wire 52 Center holder 53 Fuse 56 Side sensor 56a lead wire 57 Side holder

Claims

1. a casing that defines an internal space including a first space and a second space; a heating coil disposed in the first space; a heat sink disposed in the second space; an electronic component at least a portion of which is disposed in the second space; a partition wall separating the first space and the second space; an air intake port provided in the casing for allowing air to flow from the outside of the casing into the internal space; a first fan disposed in the internal space and configured to draw in air from the intake port and blow the air into the first space; a second fan disposed in the internal space and configured to draw in air from the intake port and blow the air into the second space; a first exhaust port provided in the casing and capable of discharging air from the first space; a second exhaust port provided in the casing and opening into the second space; An induction cooker equipped with:

2. the internal space includes a third space adjacent to the first space and in which a part of the electronic component is disposed, The induction cooker further includes a diverter that guides a portion of the air from the first fan to the first space and a portion of the air to the third space, the first exhaust port opens into the third space; The induction cooker according to claim 1.

3. an exhaust partition wall disposed between the second space and the third space in the casing, and the first exhaust port and the second exhaust port are disposed on opposite sides of the exhaust partition wall; The induction cooker according to claim 2.

4. the internal space includes a common intake space to which both the inlet of the first fan and the inlet of the second fan are open, and the intake ports are provided at a plurality of positions of the casing and open to the common intake space. The induction cooker according to claim 1.

5. The air intake includes a bottom air intake portion provided on the bottom wall of the casing. The electromagnetic cooker according to claim 4.

6. The air intake port includes a side air intake portion provided on the peripheral wall of the casing. The electromagnetic cooker according to claim 4.

7. a sensor disposed radially apart from the center of the heating coil for detecting the temperature of a cooking implement placed on the induction cooker; a coil bobbin supporting the heating coil, the coil bobbin includes a boss portion disposed at the center, a rim portion disposed on the outer periphery of the boss portion, a plurality of spoke portions radially connecting the boss portion and the rim portion, and a blocking portion blocking a space between two specific adjacent spoke portions of the plurality of spoke portions; The sensor is attached to the upper surface side of the closing portion. The induction cooker according to claim 1.

8. the first fan and the second fan are disposed on the outer circumferential side of the coil bobbin, the sensor is disposed between the first fan and the second fan in the circumferential direction of the coil bobbin. The induction cooker according to claim 7.

Images